技術情報とプレゼンテーション

Viable design alternative for the existing and fast growing UAVs which are optimized for unmanned flight is of great demand. Designing of a small scale UAV alternative to the AAI Aerosonde UAV has been considered changing the wing tail configuration of the vehicle analyzing both ... 詳細を見る

An analysis to quantify the effects of packed bed channeling in the narrow passages of the ISS (International Space Station) CDRA (Carbon Dioxide Removal Assembly) is presented. The CDRA contains two pelletized adsorbent beds to remove CO2 respired by the crew. Each CO2 adsorbent bed is ... 詳細を見る

It is frequently necessary to electrically heat gases; a convenient geometry is the familiar tube-in-shell heat exchanger, where the tube side is modified for electrical heater-rods, and the baffled shell side contains the flowing gas, as indicated in Fig. 1. However, this modification ... 詳細を見る

Catalytic micro-combustor represents an exciting area of research for portable power generation. Extensive research is being currently conducted on the design of the reactor and catalyst selection [1]. However another critical element of the design will be a recuperator to minimize ... 詳細を見る

Neste trabalho é analisado o comportamento dos perfis de temperatura e umidade e sua penetração em bobinas de papel submetidas a longos períodos de armazenagem. O modelo considera a transferência simultânea de calor e massa com o efeito Soret, mas sem o efeito Latour. O sistema é fechado ... 詳細を見る

Design and manufacture of thrusters for producing very low thrust force in the range of milli or micro newtons using micronozzles has been actively developed in the last decade. The nature of propellant flow in such micronozzles differs from that of macro nozzles. In micronozzles, ... 詳細を見る

Determination of the temperature in liquid foods may be derived by measurements or by modeling. However, the placement of thermocouple probes to record temperature in the container disturbs the flow patterns. For this purpose, Computational fluid-dynamics (CFD) offers a powerful tool for ... 詳細を見る

优先流作为结构性土壤水分入渗的主要方式，影响着作物对降水以及灌溉用水的利用效率，同时影响污染物在土壤中的迁移过程。虫洞等大孔隙是产生优先流的重要因素，准确评估优先流运动对于土壤入渗的研究具有重要意义。本文主要借助COMSOL Multiphysics软件，探索虫洞的存在对土壤水分入渗的影响。我们结合熔锡灌注法和三维激光扫描法，从田间土壤中提取到真实的虫洞三维结构，然后将真实的虫洞3D结构导入COMSOL5.5中，构建土壤入渗模型。该模型主要用到多孔介质和地下水流模块的理查德方程，其中土体主要由虫洞和土壤基质两部分构成 ... 詳細を見る

晶粒细化可有效减少金属凝固组织内部缺陷、提升产品质量。在钢铁冶金领域，通过脉冲磁场干预金属凝固过程以促使凝固组织发生细化是一类常见的手段。近年来人们针对脉冲磁场细晶机制提出诸多机理，为了揭示哪种或哪些机理起主要作用，有必要对脉冲磁场作用下金属熔体内部电磁效应进行研究。本文利用COMSOL Multiphysics中的磁场、流场（k-ε）和动网格技术，对模铸和连铸条件下脉冲磁场在圆柱形金属熔体内产生的磁场、感应电流、电磁力和流场进行仿真模拟研究。研究揭示了电磁场随时间演变规律，以及熔体在电磁力作用下的流动规律。研究表明磁场主要以竖直分量为主 ... 詳細を見る

摘要：本文通过数值模拟分析研究了高效空气过滤器的阻力与PPI、滤纸褶高之间的关系。研究表明，在一定条件下，增加PPI和增加滤纸褶高都可以增大过滤面积，减小滤纸阻力，但同时会增大高效空气过滤器结构阻力，因此滤纸存在最佳的PPI或褶间距和褶高使过滤器的阻力最低。不同的滤纸有不同的最佳结构参数。本文采用数值模拟方法对高效过滤器的阻力进行模拟，经与实测数据对比表明，误差低于10%，模拟方法可行。同时，通过对某款滤纸制成的高效过滤器进行了模拟分析，讨论了PPI和褶高对高效过滤器阻力的影响。最后建立了通用数值分析方法，通过更改相关设定参数，快速计算高效过滤器的阻力 ... 詳細を見る